Paint is a commonly manufactured and used substance with millions of tons produced and used every year. As such, paint waste, often referred to and/or in the form of paint sludge and/or powder coat waste, exceeds thousands of tons every year and can create a variety of environmental and economic problems. In addition, increasingly stringent governmental pollution regulations as well as the cost of waste disposal have led to increased concerns regarding the treatment and disposal of paint sludge.
Paint sludge can include a variety of uncured polymer resins, pigments, curing agents, surfactants and other minor formulation ingredients. In addition, the paint sludge can contain water and/or a variety of organic solvents.
Powder coating, often referred to as “powder coat”, is a type of coating process that is typically applied using a free-flowing, dry powder. The process does not require a solvent to keep a binder and filler parts in a liquid suspension form as with paint and the dry powder is usually applied electrostatically and then cured under heat to allow it to flow and form a coating layer. The dry powder can be a thermoplastic or a thermoset polymer and is the process is used for coating metals, such as “whiteware”, aluminum extrusions, automobile parts, bicycle parts and the like. However, the process can result in waste powder particles that do not get applied to a substrate and up to 5% of the dry powder as originally produced is not suited for the coating application. Therefore, a process for recycling the powder coat and/or a component made out of recycled powder coat would be desirable.